1. Field of the Invention
The present invention relates to flowmeters and more particularly to a thermal probe to be inserted into a fluid stream for measuring the flow rate.
In industrial applications where fluids are moved through conduits or containers it is essential that the flow rate be determined. It is desirable in determining flow rates that such measurement be obtained from selected locations in the flow path of the fluids and that the flow rate measuring apparatus may be easily inserted into and removed from the fluid stream at predetermined locations rather than being permanently fixed therein. Further, it is desirable that, in some instances, an interface between two liquids of different specific gravity be maintained between predetermined limits.
This invention accomplishes the desired portable features for a flowmeter by providing a relatively small probe-like device which may be manually inserted through a self-sealing probe receiving plug connected with the stream conductor without impeding the flow. The flow rate is determined by the rate of heat dissipation from the probe to the fluid stream.
2. Description of the Prior Art
Flow rate measuring devices presently in use generally have comprised a turbine type, target type, orifice or venturi type flowmeters. These devices usually contained some objectionable features, such as they are usually permanently installed or are sensitive to fluid temperature changes and obstruct flow of the fluid.
This invention eliminates at least some of the objectionable features of such flowmeters by providing a heated type flowmeter which is not permanently installed but is inserted through a vessel wall containing a stream of fluid when a measurement is desired and is removable therefrom. Further, since the diameter of the probe is relatively quite small, there is no appreciable amount of obstruction to fluid flow, the probe is easily inserted into vessels containing fluid under relatively high pressure.